SANTA CLARA, CA - DECEMBER 16: San Francisco 49ers starting quarterback Jimmy Garoppolo (10) stands on the sidelines during their game against the Seattle Seahawks in the second quarter at Levi's Stadium in Santa Clara, Calif., on Sunday, Dec. 16, 2018. (Nhat V. Meyer/Bay Area News Group)

SANTA CLARA, CA - DECEMBER 16: Football fans watch the San Francisco 49ers game against the Seattle Seahawks in the rain in the fourth quarter at Levi's Stadium in Santa Clara, Calif., on Sunday, Dec. 16, 2018. (Nhat V. Meyer/Bay Area News Group)

SANTA CLARA, CA - DECEMBER 16: San Francisco 49ers head coach Kyle Shanahan talks to the referees following a call during their game against the Seattle Seahawks in the third quarter at Levi's Stadium in Santa Clara, Calif., on Sunday, Dec. 16, 2018. (Nhat V. Meyer/Bay Area News Group)

SANTA CLARA, CA - DECEMBER 16: San Francisco 49ers' Richie James Jr. (13) is congratulated on his touchdown return against the Seattle Seahawks in the first quarter at Levi's Stadium in Santa Clara, Calif., on Sunday, Dec. 16, 2018. (Nhat V. Meyer/Bay Area News Group)

No quarterback has ever thrown for more yards in a season against the Seahawks than Nick Mullens, who went for 414 yards two weeks ago and followed with a 275-yard, one-touchdown, no-turnover encore. Dante Pettis remains hot (five catches, 83 yards) and started over Marquise Goodwin (one catch, 7 yards). Kendrick Bourne made a tough catch, dropped another, finished with two catches for 16 yards. Matt Breida caught all five of his targets. Garrett Celek scored the only offensive TD, and that 14-6 lead put the upset on track. Interior protection, not great, especially from center Weston Richburg.

Matt Breida returned from a one-game absence and fared OK as the marquee back (50 rushing yards, 46 receiving yards) until his ankle flared up (and possibly other pain) after getting belted for a 5-yard loss. Jeff Wilson Jr.’s 16-yard rumble up the middle set up Robbie Gould’s winning kick, and it atoned for his first-carry fumble. Wilson finished with seven catches for 46 yards. Fullback Kyle Juszczyk is blocking at a Pro Bowl-worthy level.

PASS DEFENSE: A

A sixth straight game without an interception or takeaway was offset by a feisty pass rush and improved secondary coverage. DeForest Buckner better earn postseason accolades, and he’s up to 11 sacks after Sunday’s pair, along with a career-high 11 tackles (four for loss). Tarvarius Moore, who typically practices as Richard Sherman’s backup on the left side, finished strong once Ahkello Witherspoon exited in the first series with a knee injury. Antone Exum’s blown tackle on the Seahawks’ second TD is a red flag that for a marquee safety in that role next season, whether it’s a free agent (see: Earl Thomas) or a rebooted Adrian Colbert. Richard Sherman complimented almost everyone on the roster after this one against his ex-team, for good reason.

Fred Warner and Elijah Lee combined for 19 tackles as a solid linebacker tandem. The Seahawks flourished best racing to the edge and Chris Carson is only the second opponent with a 100-yard rushing game. The 49ers allowed 4.8 yards per carry to the league’s top rushing attack, which tallied 168 yards, just above its average of 154.9. Marcell Harris, D.J. Reed, Arik Armstead, Mark Nzeocha, Sherman and more made noteworthy tackles.

SPECIAL TEAMS: A

Robbie Gould overcame the most difficult conditions (rain, slick turf) in his two seasons as the 49ers kicker to make not only all four field-goal attempts but the game-winner from 36 yards. Richie James Jr. embodied this as a redemption game, from muffing a punt return two weeks ago at Seattle to delivering a 97-yard kickoff return on his first touch this game. Pita Taumoepenu made the best play of his young career when he used his shoulder and not head to absolutely slam Seahawks kick returner Tyler Lockett. And don’t forget punt returner Trent Taylor, whose overtime punt return for 15 yards gave the 49ers their best starting field position all day (at their 38-yard line).

COACHING: A

Kyle Shanahan and defensive coordinator Robert Saleh motivated their players by amplifying the Seahawks’ 10-game winning streak in this series and their lopsided loss two-weeks ago at Seattle. Shanahan continues to scheme players wide open for the young Mullens, and Saleh’s defense bent but didn’t break amid a youth barrage.

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